Chelsea have some dirt at the end of their roster, but they have done a better job of getting quality at the top of their roster (Cole, Drogba, Lampard, Anelka, Terry, Essien, Cech) are all formidable.
The only problem that Chelsea have is that all of those players are entering or well into their 30s, so they do need to start thinking about replacing them and it will not be cheap, nor will it be easy to deal with numerous members of that caucus ageing on the team. They will have to make some hard decisions and shed a number of those guys and, like United, keep 2 or 3 who are vital and can be regular starters.